diff options
Diffstat (limited to 'dns.c')
| -rw-r--r-- | dns.c | 27 |
1 files changed, 22 insertions, 5 deletions
@@ -1,8 +1,9 @@ /* + * Copyright (c) 2008-2014, Simon Schubert <2@0x2c.org>. * Copyright (c) 2008 The DragonFly Project. All rights reserved. * * This code is derived from software contributed to The DragonFly Project - * by Simon 'corecode' Schubert <corecode@fs.ei.tum.de> + * by Simon Schubert <2@0x2c.org>. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions @@ -67,7 +68,6 @@ add_host(int pref, const char *host, int port, struct mx_hostentry **he, size_t char servname[10]; struct mx_hostentry *p; const int count_inc = 10; - int err; memset(&hints, 0, sizeof(hints)); hints.ai_family = PF_UNSPEC; @@ -75,9 +75,26 @@ add_host(int pref, const char *host, int port, struct mx_hostentry **he, size_t hints.ai_protocol = IPPROTO_TCP; snprintf(servname, sizeof(servname), "%d", port); - err = getaddrinfo(host, servname, &hints, &res0); - if (err) - return (err == EAI_AGAIN ? 1 : -1); + switch (getaddrinfo(host, servname, &hints, &res0)) { + case 0: + break; + case EAI_AGAIN: + case EAI_NONAME: + /* + * EAI_NONAME gets returned for: + * SMARTHOST set but DNS server not reachable -> defer + * SMARTHOST set but DNS server returns "host does not exist" + * -> buggy configuration + * -> either defer or bounce would be ok -> defer + * MX entry was returned by DNS server but name doesn't resolve + * -> hopefully transient situation -> defer + * all other DNS problems should have been caught earlier + * in dns_get_mx_list(). + */ + goto out; + default: + return(-1); + } for (res = res0; res != NULL; res = res->ai_next) { if (*ps + 1 >= roundup(*ps, count_inc)) { |